Closed Loop Water Recycling System

Electronics manufacturing requires ultra-pure water to prevent contaminants from shorting out the circuits, but the process of creating ultra-pure water is expensive. Several years ago, Lonnie Chunn, MC Assembly’s Environmental Health and Safety Coordinator, set out to develop a way to conserve that water and make the facility operation more efficient.

The Closed Loop Water Recycling System he designed now saves the Florida-based mid-tier electronics manufacturing services provider’s facility around three million gallons of water per year, cutting its water usage by 74 percent, by cleaning up and putting the ultra-pure water back into service for several cycles before finally being used to flush the facility’s toilets.

“I noticed that the water in our production discharge we sent back to the City was below 10 parts per million (ppm)” Chunn said. “By contrast the water we receive from the city is about 340ppm. It just didn’t make sense to throw away all that ultra-pure water after we spent all that money to clean it.”

To build the system, Chunn teamed up with Dave Silverman, the founder of Advanced Water Engineering Inc. Silverman is an expert in water treatment technology. Since 1989, his company has designed hundreds of water treatment systems in every industry from nuclear power to seawater desalinization, even working with NASA, building an ultrapure water system for satellite processing and a replacement ultrapure water system for filling the Space Shuttle.

“With this system, the water has been paid for once and used three times,” Silverman said. “If it’s going to cost them $10 per every thousand gallons to make ultra-pure water and we can recycle it 3 or 4 times, now it costs $2.50 per thousand gallons to make ultra-pure water and when you’re using 25,000 gallons a day, it’s hundreds of dollars a day that are saved.”

Chunn and Silverman originally worked together to develop and test a closed loop prototype system for MC Assembly’s Zacatecas Mexico facility to improve efficiency and meet the need for sufficient pure-water to ensure the quality and reliability of end products. At the same time the system reduced the plants demand and environmental impact on the local water supply.

The Mexico plant water system was a successful prototype serving as a model for the Florida system. When MC Assembly moved into its new facility in Melbourne Florida in 2015, the design had already developed from the Mexico system. Chunn and his team installed the system and maintain it. Chunn has more than 40 years of experience handling chemical health and safety issues.

George Moore, CEO of MC Assembly, said after a careful analysis of its water usage, the electronics manufacturer determined the majority of its water usage stemmed from onsite consumption of DI/RO water for the cleaning of printed circuit assemblies and the use of potable water for non-potable uses by employees.

“We immediately realized there were significant usage savings that could occur if we changed our existing model,” Moore said. “But at the end of the day, even we were surprised at just how big an impact we could have on reducing our environmental footprint. As a responsible company, it’s our job to be good stewards of the communities that we work and live in. This system allows us to do just that.”

“The electronics industry is among the heaviest regulated industries for environmental pollution control because they use metals like tin, lead, copper, nickel, silver and gold,” Silverman said. “We don’t want that released into the environment after they’ve been used for manufacturing.”

The Closed Loop Process Water Recycling System uses a combination of dual Reverse Osmosis Systems and a dual Electronic Deionizing System. Using a system of holding tanks to store the water, the company is able to reuse the water for non-potable needs in its production equipment, constantly monitoring the parts per million (PPM) of the water. Once the water is deemed non-usable for the company’s production equipment, it is diverted to another tank onsite for use in the building’s toilets.

After installing the system, Chunn made a power point presentation before the Florida Industrial Pretreatment Association (FIPA) and gave its members a tour to view the system. Randall Greer, Pretreatment Coordinator for the City of Melbourne, was one of the attendees who saw the system up close.

“It’s fairly straight forward system using reverse osmosis and the fact that he’s utilizing the waste water as a source for the restroom was a new concept for the city,” Greer said. “As far as I know, it’s the only facility in Florida that is utilizing its production waste water like this. He is defiantly cutting back on water usage just by doing that and he is still meeting all the Federal and local limits for effluent discharge.”

Greer says in addition to economic value, the system has ecologic value and could be a model for similar companies in the industry to consider.

“Defiantly, it is conserving water so that’s putting less demand on the local water supply and they’ve reduced the effluent volume of discharge by treating it to the point where they can reuse it,” Greer said. “For facilities where the main waste stream is coming from circuit board washing, I can see the benefit of using a system like this. That could be a significant cost savings by reducing the cost of the city water consumption.”

While this system could be seen as a possible model for other manufacturing companies to adopt similar technologies, there’s no “one size fits all” solution.

“You can’t just build these systems and stock them on a shelf,” Silverman said. “Each one has to be a custom built application for each company’s specific need. You need to use enough water to justify using a system like this. When you’re using 20,000 to 30,000 gallons of water a day, it actually has a significant pay back. A really large facility could save thousands of dollars a day.”

After proving the system works effectively, Chunn has been testing the system with the latest technology and plans to upgrade the system’s capabilities in the near future.